This invention relates to casting shake-out units used to separate or remove metallics from castings, slag, and dross, in a foundry, a mill, or other works, and in particular, to a rotary tumbler having helices of spaced blades and serrated blades in the attrition chamber.
In the formation of a tumbling mill, such as a casting shake-out unit, rotary separator, media drum, material drier, lump crusher reclaimer, blending drum, sand screen, or the like, the mill has generally three chambers: an intake chamber, a crushing chamber, and an attrition chamber. The intake chamber, or first compartment, receives raw castings and conglomerations from a foundry or other process. The raw castings and the like enter the intake by dumping or direct flow from a preceding process. Inwardly into the machine from the intake chamber, a crushing chamber, or second compartment, receives castings and conglomerations partially broken up by the intake.
The second compartment has a crushing means that rotates independently of the machine and rolls upon the inside surface of the machine. The partially broken up castings and conglomerations pass alongside and then under the crushing means for further reduction and separation.
Behind the crushing chamber and generally opposite the intake chamber, an attrition chamber, or third compartment, separates the metallic castings from sand and other particles. The attrition chamber collects the sand and other particles from the inside of the machine and returns them towards the intake chamber in a passageway between the outer cylinder and the inner cylinder. The attrition chamber has within it serrated toothed lifters spaced apart upon interlocking plates with holes. The lifters, at a high tumbling rotation, separate dross, slag and salt cake readily to liberate and to clean metallics and metallic oxides. Helical vanes within the attrition chamber guide metallics and metallic oxides towards an exit opposite the intake chamber while sweeping dross and sand through the attrition chamber to fall into the holes and then the passageway for removal.
There are a variety of machines and apparatuses upon the market and in use that are applied for reducing lump material to a usable consistency. For instance lumps of sand that are generally chemically bonded together just after being broken from the mold or casted part used in the casting industry can be reduced to a granular texture for its immediate reuse in the formation of a mold for further casting.
A unique aspect of the present invention is helically arranged blades in the intake chamber that both break apart lumps and advance the resulting broken materials into the rotary tumbler for further gradation and sorting. The blades are spaced apart from one another and each blade has flutes lengthwise upon its inside edge. The rotary tumbler also has a crusher that occupies the volume of the crushing chamber and has spaced apart teeth upon the leading edge of the crusher. After the crusher, helical vanes pass material through the attrition chamber and along past spaced apart blades that further separate metallics from lumps of sand and dross. These blades are spaced apart from one another and have a serrated inside edge.